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Typical of the better class of machine tool offered by Holbrook until the late 1930s, the 5"" x 24" Plain Precision Lathe Model 5P was a comparatively expensive machine. Lacking backgear and screwcutting, it was intended to compliment more sophisticated lathes and would have been of little use as the only lathe in a general-engineering workshop. Deep and very heavy, the bed had strong cross ribbing and the V and flat ways were "hand scraped to a master plate". The headstock used a hardened and ground No. 1 Morse taper spindle lapped into conical bearings made from hardened and ground steel. Adjuster collars were fitted to set the bearing-to-spindle clearance with the end thrust taken out in the (even then) old-fashioned way against a bracket bolted to the headstock's left-hand face. Three different headstocks were available: a special unit with a built-in thread-chasing attachment, a conventional one for 11/4-inch wide flat-belt (driven from a powered countershaft) and a lighter-duty, V-groove pulley type for use when the lathe was on the maker's "standards" (cast-iron legs) and driven by a round leather "gut" rope from a treadle-operated flywheel. Betraying their late 19th-century design origins the headstocks were all of comparatively light construction and had the same 1-inch 10 t.p.i nose thread and ability to pass just a 3/8" diameter bar. Of the expected type for this sort of lathe, the compound slide-rest had a 7-inch travel top slide thought formed, in this case, from an unusually long casting with (surprisingly) only two gib-strip adjustment screws. The top slide could be swiveled to any angle and its base was engraved with degree marks to 45-degrees each side of zero. The unit was clamped to the bed not by the usual hand screw but by a long lever working an adjustable eccentric clamp. The feed screws were of Acme form and ran through adjustable bronze nuts; however, as standard, no micrometer dials were fitted - though they were on the options' list. The cross-slide ways and feed screw were both covered to protect then from damage by swarf. Although not shown in the pictures, at the rear of the bed was a fitting common at the time - two useful (lipped) wooden tool trays mounted one above the other. The lower was 42-inches long by 18-inches wide and the upper 22-inches by 18-inches. In addition a wooden tool cupboard was slung beneath the bed on a pair of cast-iron rails. Like many similar plain-turning lathes of the period, the Holbrook 5P could be fitted for light production work and was available with a self-contained, bolt-on "sub-bed" assembly. Mounted on this was a compound rest where the short 13/4-inch cross travel was operated by a toggle-action lever (with front and rear stops) and the longitudinal feed by another lever working through rack-and-pinion gearing. In addition, the whole of the compound rest could be propelled along the sub-bed by a large, full-circle counter-weighted handwheel with the drive, again, through a rack-and-pinion. A rotating stop was mounted on the right-hand side of the unit but, unaccountably, had just two individually adjustable screws - not the six that were required. Mounted on the top slide was a flat-topped and T-slotted 6-station turret complete with six tool holders: Two were used to securing 1/2-inch diameter circular tools, two for pillar-style "American-style" holders for conventional turning tools and two pillar holders for broad flat tools used for forming and broaching, etc. The tailstock carried a 1 Morse taper spindle, locked by a proper screw-down pad, while the unit was secured to the bed by a captive handle working on an eccentric cross shaft. Supplied as standard with the lathe two sizes of T rest and 2 steel spanners and a Tommy bar. The power lathe came complete with a fast-and-loose countershaft unit for wall or ceiling mounting. Accessories included a swiveling vertical milling slide with 7-inches of travel table, machine vices, a 9" x 8" saw table, a fixed steady in the form of an old-fashioned "cone-boring plate" and a wide variety of collets including ring and step types with a capacity of up to 31/4 inches..
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